The Things You Should Know
by sarahanne2001
Summary: What if Faith had a secret that she never told anyone, and that secret was in danger? Would the Scoobies step up and help her?
1. Chapter 1

_**Hi everyone. This is my first attempt at the Buffy universe. I hope you all enjoy it, and as with everyone else I don't own anything. **_

Faith sighed, for six months she had been living in Sunnydale and could count the times she attended a research session on both hands. She hated anything to do with books. Faith normally avoided the meetings by claiming she needed to patrol, which was a valid excuse in her mind. This time, though, Giles had been insistent that she be there. She sighed again, this was getting boring.

"Hey Tweed what's the deal with the meeting? We gonna start it or what?" Faith asked clearly irritated.

Giles cleared his throat, "Well seeing as everyone is now here I can begin. I was reading one of the ancient texts in my library and I came across an ancient prophesy."

The scoobies rolled their eyes while Buffy said, "Just another world ending night in Sunnydale. I wonder when the big bads will think up a new plan."

Faith stood up and made as to leave, "Well you don't need me here for research, I'm gonna head out and kill some vamps."

Giles took his glasses off and began cleaning them before continuing, "If you are both done I can tell you that no research is necessary. I have already gathered all the information."

Willow looked a little crestfallen, while Xander, Buffy, and Faith all looked rather pleased. Buffy started to interrupt but Giles held up his hand to ward off her comments.

"Please allow me to finish. This is not or standard prophesy as it deals not only with the slayer but her sister. The prophesy states that tonight a group of demons will take the slayer's sister and use her as a ritual sacrifice to open a portal to a hell dimension to release a very powerful demon."

Buffy jumped out of her seat and practically yelled, "Why didn't you say that first. God I have to call Mom and Dawn, make sure their okay." Buffy ignored the others and ran into Giles' office to call her mom from the phone in there.

No one noticed that Faith also reacted to the news. See in six months of living and fighting the undead in Sunnydale, none of the Scooby's had ever tried to find out anything about Faith. If they had, they would know that Faith also had a sister, an older one who had always been there for Faith. When Faith had come to Sunnydale, her sister had decided that the Older Slayer and her Watcher didn't need to know about her. Faith's first watcher hadn't been too happy when she found out that Faith had told her sister, and the girl didn't want to cause any more trouble for Faith. Even after Faith had told her that Buffy had a group of regular people that helped out, she decided that she only wanted to be there for Faith. Faith's sister did what she always did and protected Faith by giving her a place that she could come back to that had nothing to do with monsters, human or demon. They had both started out in Sunnydale living in a rundown motel, but the older girl had quickly gotten a job and moved them into an apartment. The girls had been excited about their new home because they had never lived in a place that they could call their own before. Faith smiled slightly at the memory of their firs night in the apartment, then glanced up sharply as Buffy came barreling out of the Librarian's office.

"Mom and Dawn are both at home watching a movie with no intentions of going out. I think their safe for now."

"Now may I continue without further interruptions?" With a nod from all the teenagers present Giles continued, "Thank you, now as I was saying this demon is very strong and no mortal weapon can harm him. Therefore I think it would be best to stop the demons before they open the portal."

Buffy nodded her hand and once again rose from her seat, "Okay, Faith and I will go stake out my house and stop anything from getting too close."

Giles nodded in approval, "I think it will be a good idea for the rest of us to come along. From what I've read these demons are not very strong but there will be a lot of them, and vampires thrown into the mix."

Buffy started moving gathering weapons for the whole gang. Faith's mind was still in a fog, she kept repeating ritual sacrifice in her mind.

"Hey tweed, we sure that it's B's lil sis that the demons are after?" Faith asked with a hint of fear in her voice that none of the other picked up on.

"Seeing as Buffy is the only one with a sister I'd say it was a sure thing," Giles answered absently as he started cleaning a short sword.

Faith cleared her throat and shuffled her feet, "Well that's not entirely true." Faith scratched her head and looked at all the Scoobies before sighing, "I have an older sister."

All the Scoobies turned and looked at Faith like she had grown a second head, then Buffy laughed, "Now is not the time for joking Faith."

Faith just stared at Buffy.

Buffy took a deep breath, "Okay so you have a sister. We'll deal with why you waited to tell us until now, later. Do you know where your sister is? We'll have to split the forces."

Faith seemed to draw into herself for a second before making her decision, "No need to split forces B. Let's just stop by and get her on the way to your house. That way we can watch both."

"Are you sure Faith? If you didn't want to tell us about her will she want to go to Buffy's house?" asked the small redhead.

Faith pulled her stake out before flipping it and sticking it back in her belt, "I didn't tell you cause that's just the way she is. She won't have any problem with going to Buffy's. She'll just want to make sure I feel that she's safe."

The others seemed to accept the explanation and Giles cleared his throat, "Now that that's settled perhaps we can start?"

They all filed out of the library and piled into Giles small car. It was a tight fit, but time was of the most importance. Faith tersely gave directions to her apartment as she tried to get in touch with her sister. It was the older girl's night off and she was supposed to be at home relaxing. Faith could only assume that since she wasn't answering that she had already been taken.

As soon as the car stopped Faith took off and ran up three flights of stairs. What she saw at the top caused her to let out a feral yell. The door had been hacked off, and everything inside was in a state a disarray. It was obvious that there had been a struggle, and the younger slayer's sister had been taken.

Faith flew back down the stairs and stopped at the Scoobies, "Okay G-Man, tell me you know where they took her. Right now all I want to do is rip each one of their fucking heads off."

"Aw.. oh well I hadn't actually expected anyone to get taken. All I prepared was a defensive plan." Giles stuttered out shocked at the level of fury the young girl was displaying.

"Well aren't you fucking useless? Good thing I can always find my sister." Faith growled at the pale watcher. She pulled a necklace from under her shirt and took it off.

It was a strange little locket that made Giles feel uneasy. The feeling only grew when Faith took out a dagger and sliced her palm open. "I hope you know what you're doing. Playing around with blood magic is very dangerous." Giles said with concern.

Faith never even bothered to look up as she carefully dripped blood on the locket, "Yeah, well if any of you had tried to get to know me you'd know that I was being to be a witch before I was called. My sister is a pretty powerful witch in her own right. Right now I'm banking on that keeping her alive long enough for me to find her."

When the blood had been absorbed into the locket it started to glow a bright blue and floated out of Faith's palm. It began to move towards the street and the young slayer followed after it diligently. The others looked at each other before collectively shrugging and running after the glowing necklace.

They ran for about 5 minutes before the necklace stopped to hover over a sewer drain.

"I guess we're going down." Buffy said as Faith ripped the manhole cover off and threw it to the side like it weighed nothing.

The group climbed down to the sewers and continued for about ten more minutes without seeing any creatures of the night. The light began to dim and move slower. Faith knew that they were getting closer and motioned to the others to stay back while she took a look.

She came back and whispered to the group, "Okay my sister is in the middle of the group encased in some sort of bubble that I'm pretty sure is her doing. There are three big dudes in the middle calling the shots and about a dozen vampires, decent odds for the moment. Buffy you and I will take out the big dudes while the others take care of the vampires. If we attack from here they should be able to take them out as they approach. There's only one way I can see that leads here."

They all processed what she said and nodded, "Okay, but let's take out a couple of vampires too just to make it easier for everyone else."

Faith nodded, and everyone moved to get their weapons ready. They had prepared for fights of this nature. None of them had thought they would use it, but life on the hellmouth often threw them curve balls.

Faith took a deep breath before leading the charge. She and Buffy moved with precision and took out four vampires before anyone in the room knew what was happening. When the big guys realized what was happening they let out a roar that shook the room and startled everyone in it. The slayers shrugged it off fast and continued taking out vampires on their way to the big bads.

They took out three more vampires leaving seven. The baddies split up with one fighting each of the slayers and the third still trying to get into the shimmering bubble. The girls fought valiantly, but the creatures were a little too strong. They couldn't get the upper hand, though thankfully the scoobies had dealt with the rest of the vampires.

Faith was getting frustrated with the lack of progress, and moved towards the bubble. When she was close enough she reached out and touched the protective shield. As soon as the young slayer did that the bubble burst and the concussive force was enough to knock all of the baddies out while leaving the other alone.

"Oh, thank the Goddess Faith. I thought you would ever get here." The blonde girl said as she wobbled, "You should deal with the demons now. They're not going to be out for very long, and they're going to wake up in a very bad mood."

Faith hesitated as she watched her sister fall, but her common sense prevailed and with Buffy's help she killed the demons. When they finished she looked over to where her sister had been. Willow had made her way to the blonde and was making sure she was okay.

"Well guys I'd like to introduce you to my sister, Tara."


	2. Chapter 2

_**Hi Everyone. I really wasn't going to write anymore on this, but this chapter just wanted to be written. I'm going to leave it marked as complete because I feel it could stand on it's own. I probably won't write anymore, but I did say that when I posted the first chapter. Anyway I hope you guys enjoy it. Bare in mind that no one reads these before I post them , so all mistakes are purely mine. **_

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Tara slowly stood and made her way to Faith, "Can we get out of here F?" Tara grabbed on to the surly teenager, "That field is really hard to keep up."

The Scoobies were staring at the duo. Their looks contrasted so much that none of them would have believed they were sister except for the way they interacted. Tara was currently checking Faith over to make sure she hadn't gotten hurt.

"Is there any way out besides the way we came?" Willow asked, done with the dank smelly sewer.

Tara nodded and pointed to the far wall, "Yes, they brought me in that way. Do any of you know why they took me? I went to take the trash out and they jumped me."

"You took the fucking trash out. T what have I told you about that. You're supposed to stay inside the apartment unless I'm there to protect so something like this doesn't happen." Faith yelled shaking the blonde slightly.

Tara raised one eyebrow and crossed her arms.

"Fine, you can take care of yourself but it would make me worry less." The worried brunette conceded. Her sister had taken care of her for their entire life. Now that Faith was in the position to protect her older sister she took it very serious.

"Back to my original question, does anyone know why this happened?" Tara asked the group.

"Yes, indeed I happened to come across an ancient prophesy that foretold of the slayers sister being used as a sacrifice to the open the hellmouth. There were other parts that led me to believe that the ritual would take place tonight. I gathered the gang and we were going to protect Buffy's sister when Faith informed us of you." Giles said while polishing his glasses.

Tara looked confused, "I know I had a protective shield on and everything, but they never once tried to hurt me. All they did was bring me here."

Buffy's eyes widened, "It was all a set-up. We spent all our time coming here while they were going to my house."

The realization threw the Scoobies and Tara and Faith into a frenzy. They quickly exited the sewer and ran to Buffy's house. They were only a few blocks away from the blonde slayers house and the two slayers soon outpaced all the rest.

The group reached the house out of breath to find Buffy pacing in front of the kicked in door.

"How did they get in?" Buffy yelled frustrated.

"There are plenty of demons that do not need permission to enter someone's private residence. Luckily we do not normally deal with such creatures. Unfortunately we are dealing with it in this case. We need to go back to the library to try and discover the location of the hellmouth that they are trying to open." Giles said trying to get the group to move in the right direction.

"Actually I think I can help you find them without having to try and find anything in a book," Tara hesitantly said.

Buffy picked up the surprised girl and spun her around, "Thank god, I hate research. I would much rather find my sister. Is there anything that you need? Maybe my mom will have it."

"All I need is something that belongs to them. It'll help me create a connection with them though I've never met them." The witch told the blonde slayer.

"Is it going to be like the spell Faith used earlier?" Willow asked.

"Yeah T taught me the spell when we were younger. Actually she spelled the crystal to look for her. She can do it so that people who don't have magic can use them." Faith said when Tara walked into the house without hearing the question.

Giles turned to Faith, "Your sister sounds very powerful. Why haven't you brought her to any of the Scooby meetings? I'm sure she could have been a great asset in fight. She seems to know useful magic."

Faith shrugged and turned towards the house, "None of you ever asked about her, and she doesn't have time to go to the meetings. She's too busy working to make sure I have a place to sleep and food to eat. Most people don't want to hire someone my age."

Buffy and Tara thankfully came out of the house following two glowing objects before Giles could question her any further. Faith didn't want to tell them about her sister, they didn't deserve to know. None of them had ever hinted at any interest in her life before right now.

Everyone followed the glowing objects as it headed right towards the high school. No one was really surprised as it was the site of a known hellmouth opening. The objects led them down hallways, through corridors, and into another sewer underneath the school. Everyone was moving quickly, but they were still keeping a vigilant watch for baddies.

The hyper vigilant slayers dusted five vamps before they made it to the hellmouth. They snuck in and took a moment to assess the situation. Joyce was lying on the floor and appeared to be unharmed, other than being unconscious. Dawn was tied to the floor in the middle of a pentagram. Tara looked at the scene with confusion. Dawn's aura was like nothing she had ever seen. It was a bright green pulsing light that seemed to fill her vision. She was hypnotized by it and began moving towards the girl. Faith yanked her back and everyone gave her a weird look.

"She's… she's not normal. She's special though I don't know how. It must be why they wanted her and not me. We need to get her out of there before they hurt her. It's really important but I don't know why." Tara whispered to them, the urgency was clear in her voice.

They all turned back to the ritual and tried to figure out a plan. There was a large green demon with huge horns leading about 40 vampires. It was going to be hard to kill all the demons without the two captured women from getting hurt. This was going to be a mess.

Buffy turned to Tara with a desperate look, "Is there anything you can do with magic to help us here? We really need a miracle."

Tara exchanged a look with Faith, "We..well there is something I can do, but it's not something that I do. It can have unexpected side effects. I've only done it once, just before Faith's first watcher found us. I'd rather try and think of something else first."

The group went back to thinking before Faith finally sighed, "There's no way we could get Mrs. S and lil S without harm. There's just to many of the and not enough of us. We don't have time to think of anything else."

Tara gulped and looked around the group. The hope coming from them was too much for her and she nodded her consent. "Okay, but I'm going to need help. All the magic I've done today has drained my power. I barely have any left." The blonde turned to Willow, "Do you think I could tap into your power. Normally I would do a lengthy ritual first but as F pointed out there is no time. It's going to have to be quick and dirty and it'll probably hurt."

Now it was Willow's turn to gulp and look around at the hopeful group. Everyone really wanted to rescue the two Summers without harm. Willow slowly nodded her head even though she had no idea what to expect or how exactly she was supposed to help. Willow had only been messing around with magic for a couple weeks and couldn't even levitate a pencil yet, but Tara was a real witch and she said that Willow could help.

Tara took a deep breath, "Okay, everyone needs to be ready to move once I start. I can only deal with the vampires. I'm going to take out the closest ones and move outwards. It'll be up to the rest of you to get the ones I can't. I don't know how long Willow's power supply will last. F, you and B will need to dean with tall green and ugly."

Everyone nodded and prepped their weapons. When the group looked at the demons they could see that the ritual was starting. Tara quickly whispered a quick apology to Willow before taking her hands. Suddenly the air was crackling with magic as the girls began to glow. The group watched as the vampires started bursting into flames. The ring leader let out a roar as he tried to figure out what was going on.

Faith and Buffy jumped into the fray, killing as many vampires as they could on their way to the Big Bad. What they missed was the innocent white glow of the two girls turning an ugly black. The vampires all caught on fire and burned without becoming dust as more power than expected flowed through her. Xander and Giles grew concerned and wavered in their mission at the sight of the burning vampires, but the slayers never noticed a thing.

Xander and Giles finally regained some sense and moved to bring the two Summers to safety as the slayers continued to fight the Big Bad. Soon enough the demon was decapitated and the ritual was over, but still the witches didn't stop.

Tara had never expected Willow's affinity for black magic. The blonde was pulling in energy straight from the hell mouth and it was taking her over. Tara stood up leaving the redhead withering on the floor in pain. Tara was literally ripping the magic from her veins as fast as Willow could replace it.

The now black-haired girl floated down from their hidden ledge. Her eyes were completely black and she was focused on the celebrating slayers. Xander cried out to warn the girls before Tara could reach them. The girls looked around and finally noticed the still burning vampires. They were also quick to notice Dawn floating back to the pentagram.

Buffy raced to grab Dawn, but the pull was even stronger than the slayer. The teenager was once again tied down to the center of the pentagram. This time she was conscious, and was kicking up a fuss. Tara couldn't hear any of them and continued where the green demon had left off. Just as she was about to thrust the dagger into Dawn's chest to complete ritual, Xander finally woke Willow. He was the only one who remembered Tara telling them that she had no power. The slayers had been unable to reach her, and they were desperate to save Dawn.

When Willow awoke Tara dropped to her knees crying. Faith rushed to wrap her in a hug. She knew that Tara had been aware and struggling against what was happening. It was similar to what had happened that first night she became a slayer. The vampires had attacked and Tara had done all she could to protect her baby sister, and it had nearly cost her life.

"What the hell was that?!" Buffy yelled as she gathered Dawn up, much the way Faith had done with Tara.

Faith practically growled, "She told you something like this could happen. Bad things happen when you play with magic without understanding it or being able to control it. She only did this because we couldn't find a different way, so don't you dare fucking blame her."

Buffy glared at Faith before finally nodding her understanding. The blonde slayer was more than a little freaked at what had happened, but she was grateful that everything had worked out. They all regrouped and worked on making their way home. It was difficult because half the group was not up to walking on their own. Everyone finally made it to their homes safe and sound ready to fight again another day.


End file.
